PURPOSE:Obesity is a growing epidemic in the US and more such patients are seeking aesthetic surgery. Studies evaluating BMI as risk factor for complications following aesthetic surgery have yielded mixed results, possibly due to limited sample size or single institution experience.METHODS:A prospectively enrolled cohort of patients who underwent aesthetic surgery between 2008 and 2013 was identified from CosmetAssure database. BMI was evaluated as risk factor for major complications within 30 days after surgery. Multivariate analysis controlled for variables including age, gender, smoking, diabetes, combined procedures and type of surgical facility.RESULTS:Of the 127,961 patients, 36.2% were overweight (BMI ≥ 25). Overweight patients were more likely to be male (12.5%), diabetic (3.3%), non-smoker (92.8%) have multiple procedures (41%) and operated on in a hospital (31.3%). Complication rate steadily increased with BMI: 1.4% (BMI<18.5); 1.6% (18.5-24.9); 2.3% (25-29.9); 3.1% (30-39.9); 4.2% (≥40). Infection (0.8%), suspected DVT/PE (0.4%), pulmonary dysfunction (0.2%) was twice as common among overweight patients. Incidence of hematoma was similar in the two groups (0.9%). Incidence of any complications following abdominoplasty (3.5%), liposuction (0.9%), lower body lift (8.8%) or combined breast and body contouring procedures (4.2%) was significantly higher in overweight patients. They also had significantly more infections after abdominoplasty (1.2%), breast augmentation (0.3%) and lower body lift (2.7%). On multivariate analysis, BMI ≥ 25 remained an independent predictor of infection (RR 2.6) or any complication (RR 1.5) following aesthetic surgery.CONCLUSION:BMI≥25 is an independent risk factor for post-operative complications (especially infection) in aesthetic surgery.